#include <iostream>
using namespace std; 

class Shape {
public:
    int lineCount;

    Shape(int lineCount): lineCount(lineCount) {}
};

class Square: public Shape {
public:
    int sideLength;

    Square(int sideLength):
        Shape(4), sideLength(sideLength) {}
};

Square square(5);
//square.lineCount is 4

cout << "lineCount is " << square.lineCount;